


Tentacle Machine

by dgalerab



Series: Oikawa and Iwaizumi's Grand Adventures [4]
Category: Haikyuu!!
Genre: Birthday Sex, Christ what a tag, M/M, Tentacle Roleplay
Language: English
Status: Completed
Published: 2017-07-20
Updated: 2017-07-20
Packaged: 2018-12-04 15:18:52
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,738
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11557923
Author URL: https://archiveofourown.org/users/dgalerab/pseuds/dgalerab
Summary: Iwaizumi will do anything for his boyfriend. Even if that anything includes accommodating his boyfriend's weird alien fetishes.





	Tentacle Machine

**Author's Note:**

> Well, I've been promising this one for a while and... and here we are... I... I have no excuses, reasons or explanations.
> 
> It is what it is.

“I don’t suppose,” Iwaizumi says, trying to be subtle about the fact that he’s trapped Kenma in a corner, “that you have ever put any thought into how to realize a tentacle porn fantasy.”

“No,” Kenma says, clearly very aware that he’s trapped in a corner by a raving lunatic and not at all happy about it.

“Look,” Iwaizumi sighs. “I’m not a pervert. I’m just… dating one.”

“Uhuh,” Kenma says.

“His birthday is coming up and I… I’ve lost all my dignity, so I might as well. I will pay you. Come on, you’re the only engineer I know.”

Kenma glares at him. “Do not mention what this is for while I’m working on it. I know we both know and it’s hard to pretend otherwise, but just… don’t.”

“Alright,” Iwaizumi says.

“And I’m charging you by the hour.”

“Deal.”

“And do _not_ under _any_ circumstances tell my obnoxious boyfriend that I agreed to this.”

“Oh, gods, do I understand that.”

Kenma sighs. “I’ll… get you a list of… materials,” he says. “Now please let me leave.”

“Thank you so much,” Iwaizumi says, moving aside quickly.

Kenma flips him off on the way out.

-X-

Several weeks of very awkward work later, they’ve finally created the worst thing that Iwaizumi has ever seen. It’s certainly thorough, and when Iwaizumi remarks that this is certainly a strange project for Kenma to have finally decided not to half-ass, he responds that he wanted to be _absolutely certain_ that Iwaizumi never came to him about this again.

Iwaizumi can’t blame him.

It’s certainly an experience after that, going through all the birthday rituals for Oikawa’s birthday while knowing that the closet in their spare room currently has a large tentacle machine hidden in it (he’d had to pay Matsukawa and Hanamaki off as well to keep Oikawa distracted while he took it up).

He wakes Oikawa up with breakfast in bed, they watch go to see a crappy alien movie in the morning while the theater is almost empty, then play some volleyball in the park. Iwaizumi takes Oikawa to his favorite, fanciest restaurant.

And then finally they get home, and Iwaizumi has to face the reality that he’s created for himself.

“You look so queasy, Iwa-chan,” Oikawa says, as they climb up the stairs. “Did you eat something bad?”

“Nope,” Iwaizumi says.

“Good, because it would be awful mean of you to get all sick and gross on my birthday,” Oikawa sings.

“Ha. Ha,” Iwaizumi says. “You know after today, you better never, ever complain about how I’m not good to you.”

Oikawa gasps, grabbing onto Iwaizumi’s arm. “What did you get me?” he says. “A _spaceship_?”

“More of my dignity,” Iwaizumi says. “The last of it, I think.”

Oikawa practically clambers onto his shoulders. “Is it a sex thing? What sex thing?” he cries, loudly, in the middle of their apartment building. When Iwaizumi glares at him, he drops down, holding onto Iwaizumi’s hand with both hands. “Sorry, Iwa-chan.”

“You’ll see,” Iwaizumi says. “Sort of. You’ll be blindfolded.”

Oikawa grins at him. “Oooooh, kinkyyyyyyyy,” he whispers.

“Yeah, dumbass.” He pinches Oikawa’s cheek. “It’s for you.”

They get into their apartment purely through Iwaizumi’s force of will, because Oikawa is bouncing all around him. They’ve both had two glasses of wine each, though the walk home has sobered them both up, but Iwaizumi’s glad he’s still just a tiny bit buzzed, because this is going to come with a _lot_ of shame.

“Alright,” Iwaizumi says, catching Oikawa as he vibrates around the room. “Be a good boy and sit still for a second.”

Oikawa sits straight, saluting happily, but Iwaizumi can still see his subtle wriggling in his seat. He hold Oikawa’s face in his hands and wraps the blindfold over his eyes. Oikawa bites his lip in excitement. “Wait here for just a second,” he says, stroking Oikawa’s hair back so he can kiss his forehead.

He sets up the machine and returns to where Oikawa is still sitting, surprisingly obedient. If only he was half as well behaved when there wasn’t sex involved.

Iwaizumi blinks, pausing when he realizes that somehow “being so weird that Iwaizumi is recreating tentacle porn for his birthday” has become “well behaved” in his mind.

He sighs. “Ok, stand up,” he says, and Oikawa is on his feet in a blink.

The buttons on Oikawa’s shirt come first and the shirt drops onto the floor. Iwaizumi unbuttons Oikawa’s pants next and pushes them down with his underwear. He takes a moment for himself, just running his hands up and down Oikawa’s arms, watching the goosebumps form on his skin. “Ok,” he murmurs, to wake himself up. “That’s it. Come on.” He wraps an arm around Oikawa’s waist to lead him to the chair.

It’s shaped a little like a dentist’s chair. The fact that they’d been on a budget has made it pretty small, kind of flimsy, but there’s enough padding for it to be comfortable enough. Iwaizumi pushes Oikawa down, handing him the stupid screaming light they’ve been using each time Iwaizumi gags Oikawa. It breaks the mood entirely, but then again, as a safeword, that’s kind of its job.

“Press that twice if you need me to slow down or talk something over,” he says, guiding Oikawa’s head back onto the headrest. “Once if you need a full stop.”

Oikawa nods, and Iwaizumi leans over him, pulling his hands away and summoning his deepest, most intimidating voice. “Well then, human,” he whispers. Oikawa groans, wriggling happily in against the chair. “You’re a beautiful specimen aren’t you?”

Fuck, Iwaizumi should have definitely drunk more for this, but he was worried about doing something like this without having sound judgment.

_You’re going to owe me forever, Tooru_ , he thinks.

“Relax, human, this shouldn’t hurt,” he continues, reaching down for the restraints. The restraints, fixed onto the chair at select intervals, are covered with rubber tentacle-like sheaths which had, in turn, been dipped lube to be sufficiently slimy.

It’s a bit of a gamble, but when the first tentacle imitation touches Oikawa’s skin, he shudders, keening and curving into it. Iwaizumi smirks, fixing the restraint to the other side and switching on the tiny vibrator embedded in it so it feels like it’s moving.

There are several more just like it, wrapping around Oikawa’s chest, arms, legs… He moves the restraints across Oikawa’s body slowly, dragging them along his skin and watching Oikawa’s shifting and gasping at every little motion. His noises are little mewls, little whimpers of “please, please, pleeeease…” When Iwaizumi pulls the middle tentacle over his chest, the one with small nipple clamps embedded into it, ones that feel like suction cups (which had taken _many_ very awkward Google searches), he nearly screams. “ _Yes_ ,” he keens. “Fuck me, use me, _please._ ”

“Begging for more already?” Iwaizumi murmurs, letting his breath drift across Oikawa’s ear. Oikawa lets out a small, incomprehensible noise. “I haven’t even administered my aphrodisiac.”

Oikawa lets out a rattling groan. Iwaizumi doesn’t know why aphrodisiacs would be a kink of his when he’s ready to go all the time, but hell, they’d been in a lot of tentacle porn. _You’re so fucking weird, sweetheart_ , he thinks.

“Open up,” he murmurs. The last tentacle he wraps around Oikawa’s throat, tight enough to be just a little bit uncomfortable. The end of it he presses into Oikawa’s mouth. He presses it in quickly, letting Oikawa choke on it, then tugs it out far enough that it fills his mouth but not so far that he can’t catch his breath and swallow properly.

He waits to hear the squawking of the light, but Oikawa seems too busy suckling at the tentacle, limbs straining and twitching.

He sits back a moment to admire his work.

Oikawa’s legs, spread by the chair, are shaking against against the tentacle bonds, toes curling. His throat is working convulsively. No doubt he’d love it if the tentacle in his mouth were still choking him, but Iwaizumi couldn’t figure out a way to do it without giving himself an aneurysm with worry, and even so he’s so hard Iwaizumi’s own cock twinges in sympathy.

He must be so sensitive, with the tentacles vibrating all over his body. Iwaizumi grins.

While Oikawa enjoys himself, Iwaizumi prepares the next step, pulling on the tentacle fingergloves they’d made. Surprisingly, there had been something like this, but they’d made a replica out of silicone, which Kenma insisted would be safer for what Iwaizumi wanted to use it for.

Iwaizumi had not bothered to ask why he knew that, but he’s seen the bite marks Kenma leaves on Kuroo’s neck, and he suspects Kenma wasn’t nearly as bothered as he’d acted.

He drizzles copious amounts of lube on his gloved fingers and reaches between Oikawa’s spread legs. “Please relax, human,” he says, rubbing one finger against Oikawa’s hole, letting him feel the texture of the gloves. “I mean you no harm. Once we’ve used for breeding, you’ll be free to go.”

Oikawa moans, squirming as Iwaizumi quickly presses one finger into him. His breathing sounds painfully fast, and Iwaizumi watches the safeword light carefully, but Oikawa’s thumb doesn’t so much as twitch. He prepares Oikawa as quickly as he dares, but makes sure to stretch him well. After all, he doesn’t want to risk hurting him during the next step. However, it seems like Oikawa appreciates the quick prep. With each borderline hasty stretch, the moans crawling up his throat get closer together, higher pitched and more broken.

When he’s finally satisfied that Oikawa can comfortably take all his fingers up to the second knuckle, he steps back, trailing the gloves over the parts of Oikawa’s thighs that are still exposed, relishing in the muffled yelps it gets him. Finally, he settles between Oikawa’s legs, lining up the tentacle dildo he’d spent ages looking for. It’s fixed to an honest-to-god fucking machine. (Iwaizumi hadn’t even know that was a _thing_. Again, Kenma had suggested it.)

He presses the end of the dildo into Oikawa, stroking around it with the gloves. He can tell that Oikawa quickly realizes what the dildo is from the suction cups on the top, but he doubts Oikawa knows what’s coming next, and he’s already sobbing under the blindfold.

He switches on the machine, and watches Oikawa’s face as he realizes what’s going on. His lips tremble, and when Iwaizumi switches the speed up a setting, he starts pleading again, this time around the tentacle gagging him, like he doesn’t even particularly have the presence of mind to realize Iwaizumi can barely understand him.

“This may take a while,” Iwaizumi says, trying not to chuckle. “You will likely climax many times before I’m done with you. Please be patient.”

Oikawa’s head lolls back, choked, desperate keening noises bubbling up in his throat. His hands claw at the chair and his heels press as far down as they can go. Iwaizumi watches him shake through the first orgasm with muffled cries, then reaches down to trail the gloves over any exposed skin he can find, this time anywhere he sees fit, up Oikawa’s chest, on the soles of his feet, over the freckles on his nose…

The second orgasm comes with tears, dripping down under the blindfold,  Oikawa choking and swallowing convulsively even as he begs for more. He’s so far gone Iwaizumi doesn’t think he knows what he’s saying at all.

Iwaizumi reaches up, trailing the gloves through Oikawa’s hair. He tugs a little, wrapping the tentacles around the strands to pull. Personally, he’d rather just feel the softness of Oikawa’s hair, but he can’t say he minds seeing Oikawa fall apart, mewling and keening.

It takes a while for the third orgasm to hit, but when it does Oikawa is screaming, jolting and writhing, gagging when he swallows too much air too quickly.

Oikawa’s personal record is seven orgasms, and that’s not factoring in the oversensitivity that comes with being blindfolded, but just this once Iwaizumi is going to let Oikawa keep going as long as he wants. He knows at this point Oikawa is overstimulated beyond belief, but he’s also fairly sure that’s the whole point, the exact thing Oikawa is craving.

Despite the fact that Iwaizumi has to tilt his head to help him breath a little after his fourth orgasm, Oikawa only presses the light twice after five. Iwaizumi is glad for it, because Oikawa is shaking so hard Iwaizumi worries his bones are going to rattle apart. He reaches up to take the tentacle out of Oikawa’s mouth. “T-t…” Oikawa tries, before gasping and jolting as the machine hits something inside him just right. “Ngh… touch… mmnnnn…”

His head falls back in a silent cry as Iwaizumi finally wraps the gloves around Oikawa’s dick, jerking him quickly, until Oikawa is almost lifting off the chair, struggling like he’s been electrocuted.

The cum gets everywhere. Iwaizumi’s never seen Oikawa cum this hard.

“Shit,” he whispers, staring at Oikawa’s quivering skin in a momentary daze.

He’s shaken out of it when Oikawa moans a broken “En-enough,” and tries to curl in on himself, sobbing. Iwaizumi turns off the machine quickly, and Oikawa collapses, twitching slightly from the vibrations in his restraints. Iwaizumi undoes those as well, helping Oikawa sit up properly as he pulls off the blindfold.

He makes sure to hold him firmly, supporting him and checking his face for signs of distress. Oikawa’s teeth are clenched and he’s fumbling, shaking like jelly, but he grabs onto Iwaizumi with the kitten’s strength he has left.

“Hey,” Iwaizumi says, letting Oikawa fall into him, boneless and hiccupping with tears. He strokes his hair, letting him breathe. “You ok?”

“How am I going to top this?” Oikawa rasps, dripping snot all over Iwaizumi’s shirt. “You don’t even have enough kinks for me to top this! Iwa-chan… Iwa-chan you’ve doomed me to a life of sexual inadequacy.”

Iwaizumi laughs, hauling his utterly wrecked boyfriend into his arms. “You don’t have to win sex,” he says, not for the first time.

“I doooooo,” Oikawa warbles, almost in hysterics.

“No you don’t,” Iwaizumi says, picking him up. “Trust me, you’re a sex dream come true. So much leg… such nice shoulders…”

Oikawa’s dripping all kinds of fluids all over him, drool and tears and lube and cum. It’s kind of gross, but there’s still something cute in seeing him so mindblown he can hardly string together a coherent thought.

Oikawa wipes his nose into Iwaizumi’s shirt as Iwaizumi takes him to the bathroom, running a nice warm bath for him. He adds one of Oikawa’s bathbombs, too, and by the time he slips Oikawa into the hot, scented water, Oikawa has nearly stopped crying, instead going entirely limp.

“That’s a good boy,” Iwaizumi says, rinsing the lube out of Oikawa’s hair. “You’re so beautiful, Tooru.”

Tooru shivers, but melts into Iwaizumi’s touch. Iwaizumi lets him relax, reaching back to get some of the chocolate he’d left near the sink for this.

Oikawa lets Iwaizumi feed him, sighing out the last of his tension. Iwaizumi thinks that if he wasn’t here to hold Oikawa up, he’d probably just slip underwater and fall asleep right there.

As is, he just lays his head on Iwaizumi’s arm and nibbles at the chocolate. Iwaizumi can’t remember ever having seen Oikawa this relaxed. Maybe when they were six and had gone to the beach together and Oikawa had fallen asleep in the sun, and Iwaizumi had had to carry him back to the shade on his back because he wouldn’t get back up again.

“Is the tentacle machine ours?” Oikawa asks.

“No, I rented it,” Iwaizumi says. “Of course it’s ours.”

Oikawa nuzzles at his arm. “Incredible,” he murmurs. “I really don’t know how to top this.”

“Don’t worry about it,” Iwaizumi says. “I got to watch.”

Oikawa cracks open one eye and smirks. “So you’re into tentacles, huh?”

“I am _not_ into…” Iwaizumi starts, then sighs. “You’re a real asshole, you know that?”

“But you’re still so attracted to me it got you into tentacles,” Oikawa says, closing his eyes. He sighs. “I really was going to pull my weight if you put all this effort into tonight, but I may _actually_ be incapable of standing right now.”

Iwaizumi chuckles. “Don’t worry, I’ll get you to bed, I promise.”

Oikawa just snores.

 

**Author's Note:**

> I.
> 
> Yeah.
> 
> Nobody tell my mother.


End file.
